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Response Of Selected Warm-Season Turfgrasses And Ornamental Monocots To Short-Term, High Concentration, Ozone Fumigation, Lou Ann Mcknight Jan 2009

Response Of Selected Warm-Season Turfgrasses And Ornamental Monocots To Short-Term, High Concentration, Ozone Fumigation, Lou Ann Mcknight

LSU Doctoral Dissertations

Ozone (O3), one of the most powerful oxidants known, is phytotoxic at high levels in the troposphere, or ground-level. Effects of acute ozone exposure for two consecutive days was examined on Bermudagrass (Cynodon dactylon), centipedegrass (Eremochloa ophiuroides), zoysiagrass (Zoysia japonica), St. Augustinegrass (Stenotaphrum secundatum), Liriope muscari ‘Big Blue’, Liriope muscari ‘Aztec’, and Ophiopogon japonicus. Zoysiagrass, St. Augustinegrass, Liriope muscari ‘Big Blue’ were used in the second study based on the differential responses found in the study. Ozone induced severe visual damage to St. Augustinegrass with symptoms appearing as chlorotic streaks. St. Augustinegrass and Liriope muscari had a significant reduction in …

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Supercritical Fluid Extraction And Analysis Of Plant Oils, Tianchuan Du Jan 2009

Supercritical Fluid Extraction And Analysis Of Plant Oils, Tianchuan Du

LSU Master's Theses

Supercritical fluid extraction (SFE) of oxeye daisy (Chrysanthemum leucanthemum L.) seed, heartwood of Port-Orford cedar (POC) (Chamaecyparis lawsoniana), Alaska yellow cedar (AYC) (Chamaecyparis nootkatensis), and Eastern red cedar (ERC) (Juniperus virginiana L), and Chinese tallow (Sapium sebiferum L. Roxb. ) seed was investigated in this study and compared with other extraction methods. For the oxeye daisy seed extraction, Soxhlet extraction (SE) with hexane, microwave assisted extraction (MAE), and supercritical fluid extraction (SFE) were conducted. The results showed that as the extraction temperature decreased from 100 °C, the extraction rate increased until 30 °C using SFE. With an increase of extraction …

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Jamaican Nightshade (Solanum Jamaicense): A Threat To Florida's Hammocks, Rodrigo Diaz, William A. Overholt, Kenneth Langeland Oct 2008

Jamaican Nightshade (Solanum Jamaicense): A Threat To Florida's Hammocks, Rodrigo Diaz, William A. Overholt, Kenneth Langeland

Faculty Publications

Jamaican nightshade is a prickly, perennial, invasive shrub in central and southern peninsular Florida. It was first seen in Florida in 1930 near St. Cloud, and has since been reported at several other locations in the state. Jamaican nightshade is primarily found in wooded habitats, where it can quickly become dominant in the understory, but it also occasionally grows in isolated patches in the open. Although the distribution of Jamaican nightshade does not appear to be rapidly expanding in Florida, land mangers should be made aware of the potential of this weed to establish at new sites, and initiate control …

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Effects Of Eutrophication On Salt Marsh Root And Rhizome Biomass Accumulation, F A. Darby, R. Eugene Turner Jan 2008

Effects Of Eutrophication On Salt Marsh Root And Rhizome Biomass Accumulation, F A. Darby, R. Eugene Turner

Faculty Publications

The root:shoot ratio of grassland plants may be lower in high fertility sites than in low fertility sites as plants modify their root, rhizome and shoot morphologies (and masses) to suit prevailing nutrient availability. We conducted geographically diverse and regionally specific field sampling and measured above- and belowground plant biomasses in western Atlantic and Gulf of Mexico salt marshes to determine whether there is a similar morphological response in Spartina alterniflora, the dominant salt marsh plant. Coastal nutrient addition/enrichment, which is widespread and ongoing, may lower root and rhizome biomass, belowground production and organic accumulation in this species. Higher soil …

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Ocean Urea Fertilization For Carbon Credits Poses High Ecological Risks, P.M. Glibert, R. Azanza, M. Burford, K. Furuya, E. Abal, A. Al-Azri, F. Al-Yamani, P. Andersen, D.M. Anderson, J. Beardall, G.M. Berg, L. Brand, D. Bronk, J. Brookes, J.M. Burkholder, A. Cembella, W.P. Cochlan, J.L. Collier, Y. Collos, R. Diaz, M. Doblin, T. Drennen, S. Dyhrman, Y. Fukuyo, M. Furnas, J. Galloway, E. Granéli, D.V. Ha, G. Hallegraeff, J. Harrison, P.J. Harrison, C.A. Heil, K. Heimann Jan 2008

Ocean Urea Fertilization For Carbon Credits Poses High Ecological Risks, P.M. Glibert, R. Azanza, M. Burford, K. Furuya, E. Abal, A. Al-Azri, F. Al-Yamani, P. Andersen, D.M. Anderson, J. Beardall, G.M. Berg, L. Brand, D. Bronk, J. Brookes, J.M. Burkholder, A. Cembella, W.P. Cochlan, J.L. Collier, Y. Collos, R. Diaz, M. Doblin, T. Drennen, S. Dyhrman, Y. Fukuyo, M. Furnas, J. Galloway, E. Granéli, D.V. Ha, G. Hallegraeff, J. Harrison, P.J. Harrison, C.A. Heil, K. Heimann

Faculty Publications

No abstract provided.

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Mobile Dna Elements In Primate And Human Evolution, Jinchuan Xing, David J. Witherspoon, David A. Ray, Mark A. Batzer, Lynn B. Jorde Dec 2007

Mobile Dna Elements In Primate And Human Evolution, Jinchuan Xing, David J. Witherspoon, David A. Ray, Mark A. Batzer, Lynn B. Jorde

Faculty Publications

Roughly 50% of the primate genome consists of mobile, repetitive DNA sequences such as Alu and LINE1 elements. The causes and evolutionary consequences of mobile element insertion, which have received considerable attention during the past decade, are reviewed in this article. Because of their unique mutational mechanisms, these elements are highly useful for answering phylogenetic questions. We demonstrate how they have been used to help resolve a number of questions in primate phylogeny, including the human-chimpanzee- gorilla trichotomy and New World primate phylogeny. Alu and LINE1 element insertion polymorphisms have also been analyzed in human populations to test hypotheses about …

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Phylogenetic Conservatism And Antiquity Of A Tropical Specialization: Army-Ant-Following In The Typical Antbirds (Thamnophilidae), Robb T. Brumfield, Jose G. Tello, Z. A. Cheviron, Matthew D. Carling, Nanette Crochet, Kenneth V. Rosenberg Oct 2007

Phylogenetic Conservatism And Antiquity Of A Tropical Specialization: Army-Ant-Following In The Typical Antbirds (Thamnophilidae), Robb T. Brumfield, Jose G. Tello, Z. A. Cheviron, Matthew D. Carling, Nanette Crochet, Kenneth V. Rosenberg

Faculty Publications

One of the most novel foraging strategies in Neotropical birds is army-ant-following, in which birds prey upon arthropods and small vertebrates flushed from the forest floor by swarm raids of the army-ant Eciton burchellii. This specialization is most developed in the typical antbirds (Thamnophilidae) which are divisible into three specialization categories: (1) those that forage at swarms opportunistically as army-ants move through their territories (occasional followers), (2) those that follow swarms beyond their territories but also forage independently of swarms (regular followers), and (3) those that appear incapable of foraging independently of swarms (obligate followers). Although army-ant-following is one of …

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Modeling And Prediction Of Marine Microbial Populations In The Genomic Era, Raleigh R. Hood, Edward A. Laws, Michael J. Follows, David A. Siegel Jun 2007

Modeling And Prediction Of Marine Microbial Populations In The Genomic Era, Raleigh R. Hood, Edward A. Laws, Michael J. Follows, David A. Siegel

Faculty Publications

No abstract provided.

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Comparative Bacterial Diversity In Recent Hawaiian Volcanic Deposits Of Different Ages, Vicente Gomez-Alvarez, Gary M. King, Klaus Nüsslein Apr 2007

Comparative Bacterial Diversity In Recent Hawaiian Volcanic Deposits Of Different Ages, Vicente Gomez-Alvarez, Gary M. King, Klaus Nüsslein

Faculty Publications

Volcanic activity creates new landforms that can change dramatically over time as a consequence of biotic succession. Nonetheless, volcanic deposits present severe constraints for microbial colonization and activity. We have characterized bacterial diversity on four recent deposits at Kilauea volcano, Hawaii (KVD). Much of the diversity was either closely related to uncultured organisms or distinct from any reported 16S rRNA gene sequences. Diversity indices suggested that diversity was highest in a moderately vegetated 210-year-old ash deposit (1790-KVD), and lowest for a 79-year-old lava flow (1921-KVD). Diversity for a 41-year-old tephra deposit (1959-KVD) and a 300-year-old rainforest (1700-KVD) reached intermediate values. …

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Comparative Phylogeography Of Four Montane Bird Species In Sabah, Malaysian Borneo, Cheryl Leigh Haines Jan 2007

Comparative Phylogeography Of Four Montane Bird Species In Sabah, Malaysian Borneo, Cheryl Leigh Haines

LSU Master's Theses

Because of a dearth of modern quantitative studies of the ecology and evolution of birds, our understanding of the biogeography of the Bornean avifauna is rudimentary. Although paleogeographic evidence provides a well known mechanism for speciation in the lowlands of Borneo (i.e., repeated colonization and isolation of populations on Sunda islands caused by sea level changes), the process of speciation in montane areas is less easily explained. Knowledge about the processes responsible for montane speciation in Borneo is desirable because mountains clearly have played a key role in the evolution of the island’s avifauna, as evidenced by the relatively large …

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A Comparison Of Individual-Based And Matrix Projection Models To Applied To Fish Population And Community Dynamics, Shaye Ellen Sable Jan 2007

A Comparison Of Individual-Based And Matrix Projection Models To Applied To Fish Population And Community Dynamics, Shaye Ellen Sable

LSU Doctoral Dissertations

Matrix projection models and individual-based models (IBM) are commonly used for the analysis and management of fish populations. Matrix models break down the population into age or stage classes, while IBMs track individuals. I perform a series of quantitative comparisons between the predictions of the two modeling approaches using the IBM as the standard of comparison to demonstrate when individual variation, species interactions, and spatial heterogeneity adversely affect matrix model performance. I first evaluate the matrix approach for predicting yellow perch population responses when perch are involved in size-specific predator-prey interactions with walleye. I created density-dependent and stochastic age-structured and …

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Liana Habitat Associations And Community Structure In A Bornean Lowland Tropical Forest, Saara J. Dewalt, Kalan Ickes, Reuben Nilus, Kyle E. Harms, David F.R.P. Burslem Oct 2006

Liana Habitat Associations And Community Structure In A Bornean Lowland Tropical Forest, Saara J. Dewalt, Kalan Ickes, Reuben Nilus, Kyle E. Harms, David F.R.P. Burslem

Faculty Publications

Lianas (woody vines) contribute substantially to the diversity and structure of most tropical forests, yet little is known about the importance of habitat specialization in maintaining tropical liana diversity and the causes of variation among forests in liana abundance and species composition. We examined habitat associations, species diversity, species composition, and community structure of lianas at Sepilok Forest Reserve, Sabah, Malaysia in northeastern Borneo among three soil types that give rise to three distinct forest types of lowland tropical rain forest: alluvial, sandstone hill, and kerangas (heath) forest. Alluvial soils are more nutrient rich and have higher soil moisture than …

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Species-Habitat Associations In A Sri Lankan Dipterocarp Forest, C. V.S. Gunatilleke, I. A.U.N. Gunatilleke, S. Esufali, K. E. Harms, P. M.S. Ashton, D. F.R.P. Burslem, P. S. Ashton Jul 2006

Species-Habitat Associations In A Sri Lankan Dipterocarp Forest, C. V.S. Gunatilleke, I. A.U.N. Gunatilleke, S. Esufali, K. E. Harms, P. M.S. Ashton, D. F.R.P. Burslem, P. S. Ashton

Faculty Publications

Forest structure and species distribution patterns were examined among eight topographically defined habitats for the 205 species with stems ≥ 1 cm dbh inhabiting a 25-ha plot in the Sinharaja rain forest, Sri Lanka. The habitats were steep spurs, less-steep spurs, steep gullies and less-steep gullies, all at either lower or upper elevations. Mean stem density was significantly greater on the upper spurs than in the lower, less-steep gullies. Stem density was also higher on spurs than in gullies within each elevation category and in each upper-elevation habitat than in its corresponding lower-elevation habitat. Basal area varied less among habitats, …

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Coprophagy In A Cave-Adapted Salamander; The Importance Of Bat Guano Examined Through Nutritional And Stable Isotope Analyses, Danté B. Fenolio, G. O. Graening, Bret A. Collier, Jim F. Stout Feb 2006

Coprophagy In A Cave-Adapted Salamander; The Importance Of Bat Guano Examined Through Nutritional And Stable Isotope Analyses, Danté B. Fenolio, G. O. Graening, Bret A. Collier, Jim F. Stout

Faculty Publications

During a two year population ecology study in a cave environment, 15 Eurycea (=Typhlotriton) spelaea were observed ingesting bat guano. Furthermore, E. spelaea capture numbers increased significantly during the time that grey bats (Myotis grisescens) deposited fresh guano. We investigated the hypothesis that this behaviour was not incidental to the capture of invertebrate prey, but a diet switch to an energy-rich detritus in an oligotrophic environment. Stable isotope assays determined that guano may be assimilated into salamander muscle tissue, and nutritional analyses revealed that guano is a comparable food source to potential invertebrate prey items. This is the first report …

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Comparative Susceptibility Of Sweetpotato Weevil (Coleoptera: Brentidae) To Selected Insecticides, Tara P. Smith, Abner M. Hammond Jan 2006

Comparative Susceptibility Of Sweetpotato Weevil (Coleoptera: Brentidae) To Selected Insecticides, Tara P. Smith, Abner M. Hammond

Faculty Publications

The response of sweetpotato weevil, Cylas formicarius (F.) (Coleoptera: Brentidae), to insecticides used for its control was tested in laboratory bioassays. A glass vial bioassay technique was used to determine the susceptibility of two cohorts of sweetpotato weevil to selected insecticides. Vials were treated with methyl parathion, bifenthrin, cyfluthrin, carbaryl, and phosmet. Sweetpotato weevils demonstrated a mortality response to increasing concentrations of all insecticides tested, and our results indicated decreases in susceptibility of the Louisiana cohort of sweetpotato weevil compared with the Texas cohort for all insecticides tested. Methyl parathion was the most toxic chemical tested for both cohorts, followed …

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Phenolic Composition And Antioxidant Activity Of Sweetpotatoes [Ipomoea Batatas (L.) Lam], Malkeet Singh Padda Jan 2006

Phenolic Composition And Antioxidant Activity Of Sweetpotatoes [Ipomoea Batatas (L.) Lam], Malkeet Singh Padda

LSU Doctoral Dissertations

The influence of numerous factors on sweetpotato phenolic content and antioxidant activity was determined. Simplified, robust, and rapid methodologies were developed to quantify total phenolics and individual phenolic acids in sweetpotatoes. Quantification of total phenolic content using Folin-Denis reagent provided more reliable results than Folin-Ciocalteu reagent. Individual phenolic acids were quantified by reversed-phase high performance liquid chromatography (HPLC) and the best separation was achieved using a 5-µm, 4.6 × 250 mm column with a mobile phase of 1% (v/v) formic acid aqueous solution: acetonitrile: 2-propanol (70:22:8), pH 2.5. Methanol and ethanol provided higher phenolic extraction efficiency than acetone. In general, …

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Art Informing Science Education: The Potential Contributions Of Ornithological Illustration To Ecology Education, Vanessa Hunt Jan 2006

Art Informing Science Education: The Potential Contributions Of Ornithological Illustration To Ecology Education, Vanessa Hunt

LSU Doctoral Dissertations

Birds serve as an excellent group of organisms from which to introduce the study of ecology, being of inherent aesthetic interest to many otherwise uninterested in science, and are also ubiquitous in the immediate environment of many students. By extension, images of birds might serve as a valuable resource for the ecology educator, and bird artists – as a subset of ecologists - might provide useful models for expertise in ecology. This study examines the potential contributions of bird artists and bird art to education in ecology at the high school and college level. Eight contemporary bird artists were interviewed …

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Uncovering Bacterial Diversity On And Below The Surface Of A Hyper-Arid Environment, The Atacama Desert, Chile, Danielle Rene Bagaley Jan 2006

Uncovering Bacterial Diversity On And Below The Surface Of A Hyper-Arid Environment, The Atacama Desert, Chile, Danielle Rene Bagaley

LSU Master's Theses

The Atacama Desert in Chile extends from latitudes 17º S to 28º S between longitudes 69º W and 71º W. It has been reported that surface soils in the hyper-arid region contain low numbers of culturable heterotrophic bacteria. These soils are considered Mars-like and offer an ideal setting to investigate the application of life detection systems. Thirty-three surface sites were sampled to examine further the extent of the hyper-arid region. We also excavated four soil pits, 40 cm to 90 cm in depth, to explore subsurface microbial communities. One pit was dug in a southern region of the desert compared …

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Dendrochronological Analysis Of Productivity And Hydrology In Two Louisiana Swamps, John Blake Amos Jan 2006

Dendrochronological Analysis Of Productivity And Hydrology In Two Louisiana Swamps, John Blake Amos

LSU Master's Theses

Modified river flows and land subsidence have subjected many coastal swamp forests in the delta of the Mississippi River to greatly altered flooding, sediment, and nutrient regimes. These areas have become inundated to greater depth, duration, and frequency and either are connected to the river and receive drastically increased sediment and nutrients (riverine swamps) or have become disconnected from riverine flooding (stagnant swamps) and receive little or no sediment and nutrient input. To better understand how these changes are affecting ecosystems, dendrochronological techniques for baldcypress (Taxodium distichum L. Rich.) were used at three sites in each of two contrasting swamps …

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The Relationship Of Crime And Oil Development In The Coastal Regions Of Louisiana, Asha D. Luthra Jan 2006

The Relationship Of Crime And Oil Development In The Coastal Regions Of Louisiana, Asha D. Luthra

LSU Doctoral Dissertations

This project examines the relationship between patterns of crime and the development of the oil and gas extraction industry in the coastal regions of Louisiana. The suggestion of a link between these phenomena has often been made, but little systematic research has been conducted to determine if there is indeed a crime-oil development nexus. Limited previous research has focused primarily on the issue of “boom and bust” cycles on some forms of deviant behavior, but the data and the methods used were inadequate, and thus, the resulting conclusions were often misleading or possibly erroneous. During the course of this project, …

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Historical Fire Regimes In Southeasern Pine Savannas, Jean Marie Huffman Jan 2006

Historical Fire Regimes In Southeasern Pine Savannas, Jean Marie Huffman

LSU Doctoral Dissertations

Southeastern coastal plain pine savannas lack direct evidence of past fire regimes. As a result, uncertainty exists regarding the range of variation in frequency and seasonal timing of past fire regimes and the relative importance of anthropogenic and lightning-ignited fires. Characterization of past fire regimes is needed for effective restoration and management of these high-biodiversity ecosystems. I used dendrochronologically dated fire scars from stumps of old growth longleaf pines in a large coastal, mainland pine savanna and from dead slash pines on a small, coastal barrier island in north Florida to explore past fire regimes. In the mainland savanna, 71 …

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The Epidemiology Of West Nile Virus In Louisiana, Karen Ruth Gruszynski Jan 2006

The Epidemiology Of West Nile Virus In Louisiana, Karen Ruth Gruszynski

LSU Doctoral Dissertations

West Nile virus (WNV), a member of the genus Flavivirus transmitted by mosquitoes, first appeared in the New York in 1999. Within five years WNV was detected throughout the contiguous 48 states causing disease in reservoirs and accidental hosts alike. In Louisiana, WNV was first detected in 2001 with one human case, ten equine cases, and six dead birds reported. The introduction of WNV into Louisiana presented an unique opportunity to observe an emerging disease unfold, so a study was launched to gain insight into the epidemiology of WNV in Louisiana. The first component, an environmental predictive model for West …

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The Regulation Of Genes Involved In Trichome Development, Matthew Lloyd Brown Jan 2006

The Regulation Of Genes Involved In Trichome Development, Matthew Lloyd Brown

LSU Doctoral Dissertations

Arabidopsis thaliana is an organism that can be used as a model for most of the processes that occur in flowering plants. The leaf hairs, or trichomes, of Arabidopsis thaliana are macroscopic single cells that have been used as a model system for cell fate determination, cell expansion, cell cycle regulation, cell wall deposition, as well as other processes. Initiation of the trichome cell fate is controlled by a complex of genes including GLABRA1 (GL1), TRANSPARENT TESTA GLABRA (TTG), and GLABRA3 (GL3). This work examines the role of GL3 in trichome initiation and uses plants expressing varying levels of GL3 …

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Modeling The Effects Of Endocrine Disrupting Chemicals On Atlantic Croaker: Understanding Biomarkers And Predicting Population Responses, Cheryl Anne Murphy Jan 2006

Modeling The Effects Of Endocrine Disrupting Chemicals On Atlantic Croaker: Understanding Biomarkers And Predicting Population Responses, Cheryl Anne Murphy

LSU Doctoral Dissertations

A number of environmental stressors have been shown to interfere with reproductive and behavioral processes of fish by interfering with endocrine function. Most biomarkers of endocrine disturbance tend to be static measurements from dynamic systems making them difficult to evaluate within the context of an individual, or subtle effects that do not relate well to endpoints of ecological significance. I present an approach that uses a series of models, based on Atlantic croaker, to extrapolate laboratory results to indicators of individual and population health. First, I created a physiologically based model that simulates vitellogenesis in a female fish. The model …

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Freshwater Mussel Communities Of The Florida Parishes, Louisiana: The Importance Of Spatial Scale, Anne Raynie Bambarger Jan 2006

Freshwater Mussel Communities Of The Florida Parishes, Louisiana: The Importance Of Spatial Scale, Anne Raynie Bambarger

LSU Master's Theses

The Southeastern United States has the most diverse and imperiled freshwater mussel (Unionidae) fauna in the world. The community structure and decline of these organisms is the result of complex interactions between biotic and abiotic factors, but the limited spatial scale of most community studies has failed to elucidate the underlying mechanisms shaping community structure. Basing community assessments solely on microhabitat variables alone has lead to stark contradictions in management recommendations and opposing definitions of habitat requirements for these organisms. However, with the introduction of GIS technology into aquatic management, it is now feasible to include variables from larger spatial …

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Diversity And Structure Of Bacterial Chemolithotrophic Communities In Pine Forest And Agroecosystem Soils, J. Tolli, G. M. King Dec 2005

Diversity And Structure Of Bacterial Chemolithotrophic Communities In Pine Forest And Agroecosystem Soils, J. Tolli, G. M. King

Faculty Publications

Obligate lithotrophs (e.g., ammonia oxidizers) and facultative lithotrophs (e.g., CO and hydrogen oxidizers) collectively comprise a phylogenetically diverse functional group that contributes significantly to carbon and nitrogen cycles in soils and plays important roles in trace gas dynamics (e.g., carbon monoxide and nitrous and nitric oxides) that affect tropospheric chemistry and radiative forcing. In spite of their diverse physiologies, facultative and obligate lithotrophs typically possess the Calvin-Benson-Bassham cycle enzyme, ribulose-1,5-bisphosphate carboxylase/oxygenase (rubisCO). In an effort designed to understand the structure of lithotrophic communities in soil, genomic DNA extracts from surface (0 to 2 cm) and subsurface (5 to 7 cm) …

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Phytochrome Evolution In Green And Nongreen Plants, Sarah Mathews May 2005

Phytochrome Evolution In Green And Nongreen Plants, Sarah Mathews

Faculty Publications

Photoreceptors are critical molecules that function at the interface between organism and environment. Plants use specific light signals to determine their place in time and space, allowing them to synchronize their growth, metabolism, and development to the environments in which they occur. Thus, innovation in light sensing mechanisms is expected to coincide with adaptation and diversification. Three studies involving the well-characterized phytochrome photoreceptor system in plants indicate that much work is yet needed to test this expectation. In early diverging dowering plants, episodic positive selection influenced the evolution of phytochrome A, but little of the functional data needed to link …

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Home-Range Size, Response To Fire, And Habitat Preferences Of Wintering Henslow's Sparrows, Catherine L. Bechtoldt, Philip C. Stouffer Jan 2005

Home-Range Size, Response To Fire, And Habitat Preferences Of Wintering Henslow's Sparrows, Catherine L. Bechtoldt, Philip C. Stouffer

Faculty Publications

Henslow's Sparrow (Ammodramus henslowii) is a declining, disturbance-dependent grassland bird that winters in the longleaf pine (Pinus palustris) ecosystem of the southeastern United States. During two winters (2001, 2002), we estimated the relative abundances, movement patterns, and habitat associations of Henslow's Sparrows wintering in habitat patches differing in time since last burn (burn treatment). We conducted our study in southeastern Louisiana in Andropogon spp.-dominated longleaf pine savanna habitat. Henslow's Sparrows were most abundant in savannas burned the previous growing season, with a mean relative abundance of 2.6 individuals/ha. The most dramatic decline occurred between burn year 0 and year 1 …

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Macroinvertebrate Community Of Ecology Of Lowland, Subtropical Streams In Louisiana, Michael Douglas Kaller Jan 2005

Macroinvertebrate Community Of Ecology Of Lowland, Subtropical Streams In Louisiana, Michael Douglas Kaller

LSU Doctoral Dissertations

Freshwater ecosystems, particularly streams and rivers, have been the subject of prodigious research. Unfortunately, in comparison to neighboring regions, the Gulf of Mexico coastal plain has not received as much attention. Therefore, I collected data on the macroinvertebrates of these streams to begin the understanding of the relationships between community structure and environmental characteristics. In contrast to the hypothesized ancestral streams of these macroinvertebrates, coastal plain streams are commonly devoid of rocks leaving only woody debris as usable hard substrates and are typically lower in dissolved oxygen. I examined habitat selection by colonization of woody debris with large and small …

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Ecology And Conservation Of Louisiana Black Bears In The Tensas River Basin And Reintroduced Populations, John Farnum Benson Jan 2005

Ecology And Conservation Of Louisiana Black Bears In The Tensas River Basin And Reintroduced Populations, John Farnum Benson

LSU Master's Theses

Louisiana black bears (Ursus americanus luteolus) exist in 3 isolated populations in Louisiana and are listed as a threatened subspecies under the United States endangered species act. In order to establish a population of black bears in central Louisiana and to promote connectivity among existing populations 11 adult females and 28 cubs were reintroduced to suitable habitat on Lake Ophelia National Wildlife Refuge. We captured and monitored females in the Tensas River Basin (TRB) in northeast Louisiana for use in these reintroduction efforts and to study their ecology. Specifically, I studied the food habits, space use, habitat selection, and denning …

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